diff --git a/reference/forms/types/choice.rst b/reference/forms/types/choice.rst
index 69830ddf7c5..ba692cae826 100644
--- a/reference/forms/types/choice.rst
+++ b/reference/forms/types/choice.rst
@@ -30,6 +30,7 @@ To use this field, you must specify *either* ``choices`` or ``choice_loader`` op
 | Overridden  | - `compound`_                                                                |
 | options     | - `empty_data`_                                                              |
 |             | - `error_bubbling`_                                                          |
+|             | - `trim`_                                                                    |
 +-------------+------------------------------------------------------------------------------+
 | Inherited   | - `attr`_                                                                    |
 | options     | - `by_reference`_                                                            |
@@ -106,7 +107,7 @@ method::
         'choice_attr' => function($category, $key, $index) {
             return ['class' => 'category_'.strtolower($category->getName())];
         },
-        
+
         'group_by' => function($category, $key, $index) {
             // randomly assign things into 2 groups
             return rand(0, 1) == 1 ? 'Group A' : 'Group B';
@@ -323,6 +324,8 @@ error_bubbling
 Set that error on this field must be attached to the field instead of
 the parent field (the form in most cases).
 
+.. include:: /reference/forms/types/options/choice_type_trim.rst.inc
+
 Inherited Options
 -----------------
 
diff --git a/reference/forms/types/country.rst b/reference/forms/types/country.rst
index 1c5ddd08c9b..37c63782443 100644
--- a/reference/forms/types/country.rst
+++ b/reference/forms/types/country.rst
@@ -33,6 +33,7 @@ you should just use the ``choice`` type directly.
 |             | - `multiple`_                                                         |
 |             | - `placeholder`_                                                      |
 |             | - `preferred_choices`_                                                |
+|             | - `trim`_                                                             |
 |             |                                                                       |
 |             | from the :doc:`form </reference/forms/types/form>` type               |
 |             |                                                                       |
@@ -80,6 +81,8 @@ type:
 
 .. include:: /reference/forms/types/options/preferred_choices.rst.inc
 
+.. include:: /reference/forms/types/options/choice_type_trim.rst.inc
+
 These options inherit from the :doc:`form </reference/forms/types/form>`
 type:
 
diff --git a/reference/forms/types/currency.rst b/reference/forms/types/currency.rst
index 4ca2fdf72aa..6715253edd7 100644
--- a/reference/forms/types/currency.rst
+++ b/reference/forms/types/currency.rst
@@ -26,6 +26,7 @@ you should just use the ``choice`` type directly.
 |             | - `multiple`_                                                          |
 |             | - `placeholder`_                                                       |
 |             | - `preferred_choices`_                                                 |
+|             | - `trim`_                                                              |
 |             |                                                                        |
 |             | from the :doc:`form </reference/forms/types/form>` type                |
 |             |                                                                        |
@@ -70,6 +71,8 @@ type:
 
 .. include:: /reference/forms/types/options/preferred_choices.rst.inc
 
+.. include:: /reference/forms/types/options/choice_type_trim.rst.inc
+
 These options inherit from the :doc:`form</reference/forms/types/form>`
 type:
 
diff --git a/reference/forms/types/entity.rst b/reference/forms/types/entity.rst
index 1087d2b3bcf..70b5029ce42 100644
--- a/reference/forms/types/entity.rst
+++ b/reference/forms/types/entity.rst
@@ -32,6 +32,7 @@ objects from the database.
 |             | - `placeholder`_                                                 |
 |             | - `preferred_choices`_                                           |
 |             | - `translation_domain`_                                          |
+|             | - `trim`_                                                        |
 |             |                                                                  |
 |             | from the :doc:`form </reference/forms/types/form>` type:         |
 |             |                                                                  |
@@ -264,6 +265,8 @@ type:
 
 .. include:: /reference/forms/types/options/choice_type_translation_domain.rst.inc
 
+.. include:: /reference/forms/types/options/choice_type_trim.rst.inc
+
 These options inherit from the :doc:`form </reference/forms/types/form>`
 type:
 
diff --git a/reference/forms/types/language.rst b/reference/forms/types/language.rst
index 0156d101e09..d0bc7a637e5 100644
--- a/reference/forms/types/language.rst
+++ b/reference/forms/types/language.rst
@@ -35,6 +35,7 @@ you should just use the ``choice`` type directly.
 |             | - `multiple`_                                                          |
 |             | - `placeholder`_                                                       |
 |             | - `preferred_choices`_                                                 |
+|             | - `trim`_                                                              |
 |             |                                                                        |
 |             | from the :doc:`form </reference/forms/types/form>` type                |
 |             |                                                                        |
@@ -82,6 +83,8 @@ type:
 
 .. include:: /reference/forms/types/options/preferred_choices.rst.inc
 
+.. include:: /reference/forms/types/options/choice_type_trim.rst.inc
+
 These options inherit from the :doc:`form </reference/forms/types/form>`
 type:
 
diff --git a/reference/forms/types/locale.rst b/reference/forms/types/locale.rst
index 7a27e81ae41..2aae1712383 100644
--- a/reference/forms/types/locale.rst
+++ b/reference/forms/types/locale.rst
@@ -36,6 +36,7 @@ you should just use the ``choice`` type directly.
 |             | - `multiple`_                                                          |
 |             | - `placeholder`_                                                       |
 |             | - `preferred_choices`_                                                 |
+|             | - `trim`_                                                              |
 |             |                                                                        |
 |             | from the :doc:`form </reference/forms/types/form>` type                |
 |             |                                                                        |
@@ -83,6 +84,8 @@ type:
 
 .. include:: /reference/forms/types/options/preferred_choices.rst.inc
 
+.. include:: /reference/forms/types/options/choice_type_trim.rst.inc
+
 These options inherit from the :doc:`form </reference/forms/types/form>`
 type:
 
diff --git a/reference/forms/types/options/choice_type_trim.rst.inc b/reference/forms/types/options/choice_type_trim.rst.inc
new file mode 100644
index 00000000000..999a33ef6bc
--- /dev/null
+++ b/reference/forms/types/options/choice_type_trim.rst.inc
@@ -0,0 +1,7 @@
+trim
+~~~~
+
+**type**: ``boolean`` **default**: ``false``
+
+Trimming is disabled by default because the selected value or values must match
+the given choice values exactly (and they could contain whitespaces).
diff --git a/reference/forms/types/timezone.rst b/reference/forms/types/timezone.rst
index cf937bf80a8..4d90b16661d 100644
--- a/reference/forms/types/timezone.rst
+++ b/reference/forms/types/timezone.rst
@@ -27,6 +27,7 @@ you should just use the ``choice`` type directly.
 |             | - `multiple`_                                                          |
 |             | - `placeholder`_                                                       |
 |             | - `preferred_choices`_                                                 |
+|             | - `trim`_                                                              |
 |             |                                                                        |
 |             | from the :doc:`form </reference/forms/types/form>` type                |
 |             |                                                                        |
@@ -72,6 +73,8 @@ type:
 
 .. include:: /reference/forms/types/options/preferred_choices.rst.inc
 
+.. include:: /reference/forms/types/options/choice_type_trim.rst.inc
+
 These options inherit from the :doc:`form </reference/forms/types/form>`
 type: